Process of treating ores.



UNITED ALFRED L. PELLEGRIN, OF TUCSON, ARIZONA.

PROCESS OF TREATING ORES.

No Drawing.

2 To all whom it may concern:

Tucson, in the countv of Pima and State of Arizona, have invented a certain new and useful Improvement in Processes of Treating Ores, of which the following is a full, clear, and exact description.

This invention relates to processes of sep arating ores; and itcomprises a method of treating ores containing mineralized heavy metal salts of the oxidized heavy metal acids such as the lead salts by taking advantage of the differential attackupon the crystals or particles of such salts by sulfureted hydrogen, sulfids and the like with a preferential flotation of the attacked particles; and it more particularly comprises a method of recovering wiimdates of lead from mixed ores containing such vanadates and other lead salts, and in particular lead molybdate;

all as more fully hereinafter set forth and as claimed.

Vanadium being now in great demand there is an active search for ores containing this metal. Amongthe more valuable ores are lead ores containing lead vanadate. These (n'es,.l1o\vever, as a rule, are rather poor and they always contain many other lead salts than the vanadate. Some contain in addition to the vanadate the molybdate of lead (wulfenite). It is of course comparatively easy to separate the lead minerals from the rest of the gangue because of the great specific gravity of tlwse lead minerals ire-general; but it is less easy to separate the lead minerals from each other, since their specific gravity is much the same. It is particularly ditlicult, to separate vanadale of lead from the molybdate of lead where they occur in the same ore. Separately these two lead minerals are of considerable. of little value.

I have discovered that I can make a preterential. separation of these various lead minerals from each other by the simple expedient of selectively sullidizing their surfaces in a plurality of stages and then submitting them after each stage to flotation with oil and agitation in the usual way. These lead minerals being of oxidized nature are of course not susceptible of flotation with oil in their natural state, but become so susceptible when. superficially converted into sulfids. If all the various minerals were Specification of Letters Patent.

Application filed November 13, 1916.

mg the lead vanadates as a residue.

value, but in admixture they are Serial no. 131,015.

converted into sulfids superficially no separation would of course be possible by flotation; but I have found that these various lead minerals when exposed to the action of a limited amountof sulfureted' hydrogen, of sodium sulfid, etc., are not all attacked at the same rate. The action of the sulfur is preferential. ind I find that by proper regulation of conditions with an ore containing lead carbonate, lead oxid and other lead salts together with lead vanadate, the lead vanadate is the last to be attacked by sulfur compounds. 'lherefore in any such mixture by applying a suitable amount of a sulfur reagent, tl1e amount being such thatthe vanadateis not attacked, and then floating with oil and agitation in the usual way, the

Patented July 17,1917.-

other lead minerals maybe floated and thereby separated from the lead vanadate. If the mineral also contains lead molybdate, on treatment with a small amount of sulfur as before .in the flotation, the lead vane-date and lead molybdate will be left in the residue. ()1) again preferentially sulfidizing, the lead inolybdate may now be floated leav- In other words, by performing the sulfidizing and flotation in successive steps, I can separate such a complex 1 ad ore into a plurality .of different mineral products of good commercial grade. p

In a practical embodiment of the present invention treating a highly complex ore carrying lead carbonate, lead oxid, lead molybdate and lead vanadate together with gangue. I first treat the ore in any of the usual ways and by any of the usual methods of concentration, wet or dry, to separate the gangue and to make a concentrate consisting of the stated lead minerals. If the amount of gangue is inconsiderable thispr,e liminary treatment may of course not be necessary. As a rule grinding should be carried only so far that distinct crystal faces of the minerals to be separated still exist.

llaving the pure concentrates in a wet condition, I may next blow sulfureted hydrogen through the pulp; or I may mix a little sodium sulfid in solution with such pulp.

In either event sulfidizing is sto )ped as soon as the mineral which 18 desire to float 1s attacked and before. the other minerals ex-. hibit signs of action.

The mixture is now mentioned I ordinarily float the lead carbonate and oxid together. This now leaves me a residue containing lead molybdate and lead vanadate. As stated, the mixture of these two minerals is worth very little, but severally they are very valuable. This residue I again sulfidize, ceasing the treatment before the particles of lead vanadate are materially afl'ected. On now adding oil and water and agitating the wulfenite or lead molybdate may be selectively floated, leaving the lead vanadate in the residue as a material of commercial grade.

Any suitable oil or process of flotation may be applied in the flotation operation and any suitable apparatus may be e1nployed. In the preliminary concentration of the ore any ordinary method may be used.

Having thus described my invention, what I claim is 2,

1. In the" separation of lead vanadate from other leadxminerals the. process which comprises sulfidizingthe surfaces of particles of ,such/ other lead minerals,- discontinuin the treatment prior to' substantial attaci c of the vanadate and then separating theattacked mineral from the lead vanadate by flotation.

2. In the separation of lead salts of heavy metal acids from other lead minerals in a lead ore, the process which comprises sulfidizing the surfaces of such other minerals, discontinuing the sullidizing prior to the attack on the particles of the lead salts of such heavy metal acids and subjecting the mixture to flotation to remove the attacked particles.

3. In the separation of lead molybdate and lead vanadate from other lead minerals in complex ores containing the same, the proccss which comprises submitting the ore mixture to a sulfidizing treatment until the surfaces of the particles of such other lead minerals are attacked, submitting to flotation to remove the attacked particles, again sulfidizing the residue to such an extent as to attack the lead niolybdate only and subjecting the mixture to flotation to obtain the lead molvbdate as floats and lead vanadate as a resi me.

In testimony whereof, I hereunto aflix my signature in the presence of two witnesses.

ALFRED L. PELLEGRIN. Witnesses:

PAUL GATLIN, M. GATLIN. 

